The present invention relates generally to a method and apparatus for processing snack food chips. More particularly, the invention relates to a method and apparatus for stacking curved tortilla chips in a uniform stack which then can be packaged neatly and compactly, e.g., in a cylindrical can or other sleeve-type container.
Tortilla chips are one of the more popular types of snack food products and have come to be associated with having a triangular shape. Additionally, snack food chips which are used for dipping, e.g., potato chips, tortilla chips, or corn chips, preferably are curved to enhance the scooping ability of the chip as well as to add strength to the chip.
With respect to packaging, a stacked arrangement of snack food chips has been found to be popular. The typical triangular shape of a tortilla chip, howeverxe2x80x94particularly a curved tortilla chipxe2x80x94previously has prevented tortilla chips from being packaged in a stacked arrangement in an efficient, automatic process.
The present invention provides a method and apparatus for automatically arranging curved, triangular snack food chips such as tortilla chips in a neat, compact, stacked arrangement which is suitable for packaging the chips in a cylindrical can or other sleeve-type package. According to the invention, the chips are transported along a vibrating U-shaped chute, oriented in an alternating arrangement. The vibrating U-shaped chute automatically ensures both proper orientation and positioning of the chips in that the chips slide laterally such that their centers of gravity are at the bottom of the chute and such that base edges of the triangular chips are oriented parallel to the longitudinal axis of the U-shaped chute. The chips then fall into a W-shaped vibrating chute, with the chips originally having one orientation automatically being caused to fall into the trough constituting one half of the W-shaped chute and the chips having the opposite orientation automatically being caused to fall into the other trough constituting the other half of the W-shaped chute.
The chips then travel along the W-shaped chute by sliding along their base edges, i.e., with their opposite, upturned apices pointing perpendicular to the direction of travel of the chips. The tortilla chips are then caused to rotate by 120xc2x0 such that the upturned apices xe2x80x9cleadxe2x80x9d as the chips continue to progress. This configuration permits the chips to slide into nested, stacked relationship automatically, in which arrangement the chips can be packaged easily in a stacked configuration.
Thus, in a first aspect, the invention features a method of stacking curved, generally triangular tortilla chips for subsequent packaging, e.g., in a sleeve-type package. The method entails transporting a succession of the chips along a direction of travel, and while transporting the chips, causing them to be oriented such that their apex corners point in the direction of travel. The chips are then caused to become stacked automatically by virtue of the apex corner of one chip sliding up and over the base edge of the preceding chip in the succession such that they come into a stacked, nested arrangement automatically.
In preferred embodiments, the chips are oriented properly by sliding down a J-slide from one conveyor to another. Alternatively, the chips can be allowed to tumble over the end of the first conveyor onto the second conveyor.
In another aspect, the invention features a method of segregating the chips into separate lines or successions of chips based on the direction in which the chips point (as indicated by their upturned, apex corners). The method entails transporting the chips in a given direction of travel and causing the chips to be oriented such that the line about which each is curved is substantially parallel to the direction of travel. The chips are also caused to move laterally, relative to the direction of travel, such that their centers of gravity become generally aligned. (This may be done simultaneously with the step of causing the chips to be oriented such that their lines of curvature are substantially parallel.) At this point, the straight base edges of the chips pointing in one direction will all be aligned, and the straight base edges of the chips pointing in the opposite direction will all be aligned, and the apex corners of the chips pointing in one direction will extend laterally beyond the base edges of the chips facing in the opposite direction and vice-versa. The chips are then segregated into two separate conveyor troughs by being tripped or partially flipped by means of their apex corners into the troughs, with the chips pointing in one direction going to one conveyor trough and the chips pointing in the other direction going to the other conveyor trough.
In preferred embodiments, the chips are both oriented and caused to move laterally simultaneously by transporting them along the bottom of a vibrating U-shaped chute, the radius of curvature of which preferably matches the radius of curvature of the chips. Additionally, the conveyor troughs are provided by means of a W-shaped chute, and the chips are tripped or partially flipped into one side of the xe2x80x9cWxe2x80x9d or the other.
In combination, these two aspects provide a method of segregating and stacking curved, generally triangular chips such as tortilla chips.
In another aspect, the invention features an apparatus for segregating and stacking for subsequent packaging a succession of curved, generally triangular chips. The apparatus features a first, vibratory, generally U-shaped conveyor chute which feeds into a second, generally W-shaped conveyor chute. The W-shaped conveyor chute has means for rotating the chips by about 120xc2x0, and the apparatus includes two accumulator conveyors which receive chips from the W-shaped conveyor chute and which automatically accumulate and stack the chips in a nested, stacked arrangement.
In preferred embodiments, the first, U-shaped conveyor chute includes a pair of fingers extending from its downstream end, and the fingers are positioned above the two troughs of the second, W-shaped conveyor chute to trip or flip the chips into one trough or the other depending on the orientation of the chips. Additionally the W-shaped chute preferably is vibratory, as are the accumulator conveyors. The means for rotating the chips can be J-slides which transfer the chips from the troughs of the W-shaped chute to the accumulator conveyors or, alternatively, the chips can be allowed to tumble over the edge of the end of the W-shaped chute onto the accumulator conveyors.
By employing the various inventive concepts disclosed herein, it is possible to produce curved, triangular chips such as tortilla chips in alternating directions (which is the most efficient way to make tortilla chips) and then stack them automatically, conveniently, and reliably to be packaged in a popular sleeve-type container.